Nothing makes poor air quality more apparent than smog, orange skies, and a smoke-filled haze that you can barely see through. But unsafe air is often much less visible. As it stands, 91% of the population lives in places where the air quality falls below the World Health Organization’s guidelines. That’s why investing in an air purifier is a logical step to take to protect your home—and the people within—from harmful pollution.

But when it comes to air purifiers, there are a lot of misconceptions about their effectiveness and whether or not they are worth the money. The CDC recommends using a freestanding indoor air filter to protect from the effects of wildfire smoke and other pollution. They are effective. And they can be worth the investment—especially if they’re from Dyson.

Dyson employs more than 350 engineers, chemists, and research scientists who have spent nearly three decades dedicated to air science. The brand’s purification technology, currently in its sixth generation, is among the best on the market. Dyson’s line of air purifiers includes a personal miniature purifier ($350), cooling room purifiers (from $470), heating and cooling purifiers ($670), and even humidifying purifiers ($820).

[Photo: courtesy Dyson]

Each model eliminates 99.97% of particles as small as 0.3 microns (which is 233 times smaller than the width of a human hair, for scale). The line achieves this by using fully sealed HEPA filters and three intelligent sensors that track, in real time, the levels of pollution in your home. These sensors detect particulates (like dander and dust) and gases (like nitrogen dioxide and industrial emissions), while also monitoring temperature and humidity. Whenever your purifier detects a certain level of pollutants, it will activate and purify the air.

Dyson’s purifiers are certified by the Asthma and Allergy Foundation of America. And the National Psoriasis Foundation recently certified the Dyson Pure Humidify+Cool three-in-one purifier, humidifier, and fan—the first machine of its kind to receive this recognition.

Keeping damp equipment like a humidifier clean—while still making your air cleaner—isn’t easy, according to David Hill, Dyson engineer and design manager. He explains how it works: “First the water in the tank at the base of the machine is pumped up through a column. In this column we have a highly reflective PTFE tube and a UV-C light. Water is exposed to the light several times to kill 99.9% of bacteria in the water. The water is then deposited onto a mesh evaporator. As an added layer of defense, we have woven silver into the mesh evaporator, which has biostatic properties. Meanwhile, air is drawn in through the shroud around the base of the machine and passes through our filter system.”

The Pure Humidify+Cool has two filters: a HEPA filter that captures particles as small as 0.3 microns and an activated carbon one that captures gases and odors. “The air is purified as it passes through the filters and then it travels through the evaporator where it picks up moisture,” Hill explains. “Then the purified and moistened air is projected into the room through the amp.”

[Photo: courtesy Dyson]

Air purifiers with sealed HEPA filters provide added protection from bacteria, viruses, smoke, dust, and pollen as well as keep the air clean of everyday pollutants found in our homes such as dander from pets, fumes from gas stoves, and volatile organic compounds (VOCs). The Dyson Pure Plus collection of purifiers ups the ante and utilize extra-large glass HEPA filters, made with 29 feet of borosilicate microfibers, folded into more than 238 pleats. The Dyson Pure Cool, Pure Humidify+Cool, and Pure Hot+Cool designs all feature powerful air flow that delivers 77 gallons of fresh, safe, ready-to-breathe air per second into the room.

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